Speed governors



July l0, 1956 R. J. IFIELD SPEED GOVERNORS Filed Sept. 2l, 1953 IIII IHIIIII Il United States Patent C) SPEED GOVERNORS Richard Joseph Iiield,Dural, New South .Wales Australia, assignor to Joseph Lucas (Industries)Limited, Birmingham, England Application September 21, 1953, Serial No.381,313

2 Ciaims. (ci. 264-6) This invention relates to speed governors of thetype in which movement of a part under the action of centrifugal forceis utilised for actuating a valve, electric switch or other controllingmeans, the object of the invention being to ensure prompt action of thegovernor and to minimise hunting.

The invention comprises the combination of a hollow rotary body, a partmovable by centrifugal force, and a helically-shaped member contained inthe said body and connected to the said centrifugally movable part, thearrangement being such that under the action on the said helicallyshaped member of a liquid contained in the said rotary body asupplementary force is exerted on the said part during acceleration ordeceleration of the rate of rotation of the body.

The accompanying drawing is a sectional view illustrating one example ofa speed governor in accordance with the invention for controlling thesupply of motive liquid to a servo-mechanism which controls the rate ofsupply of liquid fuel to a prime mover.

Referring to the drawing, there is mounted within a housing a a hollowcylindrical rotary body b which is rotated by a driving spindle c.Within this body is contained at least one centrifugal mass d, butpreferably two or more similar masses are provided. Each such mass iscarried by a pair of spring, or spring-loaded, arms e one of which isattached at one end to one end of the rotary body b. Also within therotary body is contained a hollow cylindrical and axially slidablemember f having formed around it a iin g of helical form. To thismeinber is attached one end or ends of the other arm or arms e, thearrangement being such that radial inward or outward movement of thecentrifugal masses is accompanied by a corresponding axial movement ofthe said member f.

The helically nned member f may have several convolutions, or a singleconvolution. Alternatively any other equivalent helically shaped bodymay be used.

The helically finned member f is attached to a sleeve h which isslidable on a hollow and ported axially arranged valve stein i forcontrolling the flow of motive liquid through the said housing, the stembeing axially adjustable by a manually operable cam j and being loadedby a spring k.

The rotary body b is filled with which normally rotates with, and at thesaine speed as, the body, but which owing to its intertia can rotateindependently of the body during acceleration or deceleration.

When, as shown in the drawing, the governor is required to control theaction of a servo-motor which in turn is required to control the supplyof motive fluid to an engine, the liquid contained in the governor isthat required to operate the servo-mechanism. In the drawing anyconvenient liquid there is represented diagrammatically a known form ofservo-mechanism. This comprises a cylinder m containing a piston n whichis loaded by a spring o. From the piston extends a rod p for actuatingan engine controlling means, such as the means for varying the output ofa fuel pump, a fuel-controlling throttle, a fuel bypass or other means.Motive liquid for the servomechanism is admitted at q and both ends ofthe cylinder are in communication with each other through a restrictedorifice r. At the end of the cylinder remote from'the liquid inlet isprovided a vent s which is connected by a pipe to the inlet t of thebody part of the governor. When flow through the vent is stopped by thegovernor valve above described the spring o moves the piston to theposition of maximum fuel `supply to the engine. On opening the valve,the preponderating liquid pressure then acting on the left hand side ofthe piston moves the latter in the direction for restricting the fuelsupply.

The action of the governor above described is such that so long as thespeed of the engine remains below a given rate determined by the settingof the cam j, the sleeve h prevents ow of liquid from the servomechanism. But when that speed is exceeded the sleeve moves upwardly toa position in which it permits flow of liquid from the servo cylinderthrough the hollow stem i, rotary member f and holes in the rotary bodyb to the interior of the housing a, and thence through a dischargeoutlet u, and so enables the servo mechanism to restrict the fuelsupply.

The inode of action of the governor is such that during change of speed,with accompanying outward or inward movement of the centrifugal massesd, a relative rotational motion occurs between the liquid and the finnedmember f, causing an axial force to be exerted on the said member whichantecedes the action of the centrifugal masses, and so ensures promptaction of the governor: it also minimises hunting. This action ceaseswhen the rotation resumes a uniform rate.

The essential feature of the invention resides in the combination of theliquid-operable helically finned member with a part responsive to theaction of centrifugal force, and the invention is not restricted to theexample or purpose above described, as it may be applied in essentiallythe same manner to other forms of speed governing mechanisms dependenton the action of a rotary mass or masses movable by centrifugal force.Moreover, instead of actuating a valve, the governor may be adapted toactuate an electric switch or any other control means required to bemoved from one position to another with a change of speed.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A speed governor comprising in combination a rotary liquidreceptacle, a rotary and axially movable member mounted in saidreceptacle, and at least one centrifugally operable mass connected tosaid receptacle and member so that rotation of said receptacle isaccompanied by rotation of said mass and member, and axial movement isimparted to said member in response to movement of said mass bycentrifugal force during rotation of said receptacle, said member beinghelically shaped to enable liquid contained in said receptacle to exerton said member a supplementary axial force during acceleration anddeceleration of the rate of rotation of said member.

2. A speed governor comprising in combination a Patented July 1o, i956.

housing, a rotary liquid receptacle in said housing, a rotary and`axially movable memberrnounted in said 're eeptacle, and at least onecentrifugally operable mass connected to said receptacle and member sothat rotation of said receptacle is accompanied by rotation of said massand member, and axial movement is imparted to said member in response tomovement of said mass by centrifugal force during rotation 4of saidreceptacle, said member consisting in part ofat least-one helical iinfor enabling liquid contained in :said receptale to exert on said membera supplementary axial force which antesaid member during accelerationand deceleration of the rate of rotation of said member.

References Cited in the file of this patent UNITED STATES PATENTS1,130,659 Baldwin Mar. 2, 1915 2,247,989 Cita July l, 1941 2,472,181Werth n. June 7, 1949

